Circuit interrupter



0. H. ESCIHHOLZ CIRCUIT INTERRUPTER Filed Aug. 18. 1921 INVENTOR Otto hf fschllo/z ATTORNEY,

Patented Apr. 24, 1923.

UNITED STATES PATENT DFFHIE.

HOUSE'ELECTRIC AND MAITUF SYLVAN IA.

.ACTURING COMPANY, A CORPORATION OF PENN- CIRCUIT INTERRUPTER.

Application filed August 18, 1921. Serial No. 493,238.

To cZZ whom it may concern Be it known that I, OTTO l-l. ESCHHOLZ, a citizen of the United States, and a resident of Vilkinsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Circuit Interrupters, of which the following is a speci fication.

My invention relates to circuit interrupters and particularly to means for reducing the currenttraversing the same before the circuit is completely opened.

One object of my invention is to provide a member that is saturated with an electrolyte which is adapted to evaporate when current is directed therethrough, to change the resistance of the member.

Another object of my invention is to provide a device of the above-indicated charactor that shall be adapted for use in connection with resistance-type circuit interrupters for dissipating the energy of the circuit before final interruption thereof.

Still another object of my invention is to provide a device of the above indicated character of relatively large capacity and one wherein the operation is more uniform than in devices of the type heretofore employed.

A further object of my invention is to provide a current-limiting device that shall be simple and inexpensive to construct and that shall be inherently resetting in its op eration.

In practicing my invention, I provide a plurality of cloth or fiber members that are electrically connected across the terminals of an auxiliary circuit interrupter and pro vide, also, means whereby the fibermembers may be supplied with an electrolyte such as calcium bichloride that is adapted to saturate the fiber members by capillary attraction. When the circuit through the auxiliary interrupter is opened, current is shunted through the fiber members to evaporate the salt solution and to thereby increase the resistance of the shunt circuit. In this manner, the current is limited so that the main circuit interrupter may be opened without injury thereto. Such a structure is shown and described in the application of Joseph Slepian, Serial No. 242,625, filed June 29, 1918, and which is assigned to the Westinghouse Electric and Manufacturing Company.

More particularly stated, my invention also comprises means for dividing a fiber member into a plurality of independent portions that are separated by metal plates which are corrugated longitudinally. These plates permit the escape of globules of gas or vapor that may be formed and which have a tendency to reduce the resistance offered by the fiber elements.

Heretofore, it has been proposed to employ a plurality of independent resistor units in order to secure a device of greater capacity, because merely by doubling the cross sectional area of a fiber member, it is not possible to thereby secure a corresponding increase of capacity owing to the tendency towards the formation of internal arcs.

In separating the wick members by corrugated metal plates, I not only provide means for the escape of globules of gas but, I am also enabled to secure, in a resistance unit, a capacity proportional to the size of thefiber members employed.

Figure 1 of the accompanying drawing is a diagrammatic view of a circuit interrupter embodying my invention.

Fig. 2 is a plan view of the resistance element employed by me.

The circuit interrupting system comprises a main circuit interrupter 3 and an auxiliary circuit interrupter 4 that are connected in series with a conductor 5 that is to be protected. The interrupter 3 is provided with a trip coil 6 that is connected in series with a trip coil 7 of the circuit interrupter 1'. The trip coils are connected to the transformer 8, and the coil 6 is provided with a dash-pot 6.

A. current limiting device 13 is connected in shunt with the circuit 4: for the purpose of receiving the current when the circuit interrupter 4 is opened, and for so reducing the current that the circuit-interrupter 3 may be safely opened.

he current that traverses the device 13 passes through a conducting terminal 9. fiber or cloth members 10, corrugated metal blades 11 and a conductor terminal 12.

The fiber members 10 are impregnated, by capillary attraction. with a salt solution 14, such as calcium bichloride, that is contained in a tank 15.

When an overload traverses the circuit 5, the trip coil 7 will operate to trip the circuit interrupter 4: thus permitting current to traverse the shunt circuit. hen the current traverses the fiber member 10 suiiicient heat will be liberated to evaporate the salt solution that is contained therein and to thus increase the resistance to the flow of current therethrough. v Vhen the current has been reduced to a relatively small value, the dash-pot 6 will permit-the trip coil 6 to trip the circuit interrupter 3 to thereby completely open the circuit 5. T he time setting of the dash-pot 6 is such that it will not permit the opening or the interrupter before the device 13 has functioned.

It will be apparent that the corrugations of the metal plates 11 extend in a longitudinal direction and that channels are thereby provided through which globules of gas may escape, and that the corrugations also exercise a dissipating eiiect on the vapors that are formed in the fiber members when cur rent is being directed therethrough.

In order to secure the proper channel effect, it is preferable to arrange the members 11 with their respective corrugations in staggered relation as indicated in Fig. 2.

It will be understood that my invention is not limited to the particular form of tripping device shown, nor to the particular means described for the division into sections of a fiber member or members, or similar devices, but that various other means for the division of a single current limiting device into sections may be employed without departing from the spirit of the invention as defined in the accompanying claims.

I claim as my invention:

1. A resistance device comprising a pair of spaced terminal members, a plurality of spaced capillary members interposed therebetween, and corrugated members bridging the spaces between the capillary members, the capillary members bein saturated With a salt solution that is adapted to evaporate when current traverses the member, to thereby increase the resistancethereof to the passage of current.

52. A resistance device comprising a plurality of porous members, means for supplying a salt solution to said members, and

means for bridging said members but permitting circulation of air therebetween.

3. A resistance device comprising a plurality of porous normally non-conducting members, means for supplying a salt solution to said members, and channeled con-' ducting members interposed between adjacent surfaces of the porous members.

In testimony whereof, I have hereunto subscribed my name this 22nd day of July,

OTTO H. ESGHHOLZ. 

